“You’ll come back out a different person. That’s for sure,” Jackson said. "It’s hard to explain when you have those kind of situations and how you react when your instinct is to run for your life. Her screams were so loud, it almost willed me to go back and see what I can do.”

Jackson helped carry his co-worker to the roof of Building 197, where they were rescued via helicopter.

He says he suffers with bouts of memory loss and painful flashbacks.

"At certain times, we can still hear him shooting underneath us," he said.

Jackson said those wounds were opened up even deeper when he watched coverage of Wednesday's mass shooting at Fort Hood in Texas. Four people, including the gunman, were killed and more than a dozen were injured.

"You start learning about what you can and can't do and then you find solutions to it," Jackson said.

He and several other survivors of the shooting will be honored at the Washington Nationals' home opener Friday afternoon.

Jackson is hoping Friday's new memory replaces that dark day in September.